System and method for measuring and recording latency in internet protocol networks

ABSTRACT

A system and method for measuring and recording latency in data networks. The system and method can be used to measure and record latency in a Simple IP network or a Mobile IP network. One embodiment of the present invention is a system and method for measuring latency between a first device and a second device, the first and second devices communicating in accordance with a communications specification. The system and method comprises the second device transmitting, during a communication session, a message to the first device; receiving a response message from the first device; computing an elapsed time from transmission of the message to receipt of the response message to determine the latency; and recording the latency in a latency parameter. The message and the response message are provided by the communications specification.

FIELD OF THE INVENTION

The present invention relates generally to data networks, such asinternet protocol networks, and more particularly, to a system andmethod for measuring and recording latency in a data network.

BACKGROUND OF THE INVENTION

While tools do exist today which measure latency in a data network, suchas a wireless data network, this functionality is not integrated intothe set of services provided by wireless networks today. Furthermorethese tools are used to measure latency at the equipment level, not atthe user session level.

In wireless networks, a mobile station is connected to a radio accessnode via a wireless or radio frequency (RF) network. The radio accessnode is then connected to the data network (e.g., the Internet)typically via a wire-line network. The radio frequency network isfrequently the most unreliable part of the end-to-end connection. Badconnections or a high volume of voice calls in the sector will affectthe quality of data calls and thus increase latency. Thus, it isimportant for service providers to be able to measure wireless accesslatency at the user session level from the mobile station to the radioaccess node (i.e., the packet data serving node or PDSN).

Accounting information is generated for data calls, providinginformation such as the number of bytes transferred for a given datasession and the session duration. However, currently nothing isgenerated which measures user experience on a per user, per sessionbasis.

Accordingly, there is a need for a system and method for measuring andrecording latency in a data network on a per user, per session basis.

SUMMARY OF THE INVENTION

A system and method for measuring and recording latency in datanetworks, such as internet protocol (IP) networks. The system and methodcan be used to measure and record latency in a Simple IP network or aMobile IP network. One aspect of the invention utilizes control planemessages for measuring latency to avoid the messages associated with thelatency measurements from being billed to the user.

One aspect of the invention is a system and method for measuring andrecording latency between a mobile station (MS) and a packet dataserving node (PDSN) or foreign agent (FA). Another aspect of theinvention is for measuring and recording latency between the PDSN/FA anda home agent (HA). Latency information can be made available forbilling, statistical and reporting purposes.

One embodiment of the present invention is a system and method formeasuring latency between a first device and a second device, the firstand second devices communicating in accordance with a communicationsspecification. The method comprises the second device transmitting,during a communication session, a message to the first device; receivinga response message from the first device; computing an elapsed time fromtransmission of the message to receipt of the response message todetermine the latency; and recording the latency in a latency parameterin a data record. The system comprises a first device and a seconddevice adapted for communicating in accordance with a communicationsspecification. The second device is adapted for transmitting, during acommunication session, a message to the first device; receiving aresponse message from the first device; computing an elapsed time fromtransmission of the message to receipt of the response message todetermine the latency; and recording the latency in a latency parameterin a data record. The message and the response message are provided bythe communications specification.

Another embodiment of the present invention is a system and method,performed by a packet data serving node, for measuring latency. Themethod comprises the packet data serving node storing a first starttime; transmitting, to a mobile station, a Link Control Protocol Echomessage; receiving a Link Control Protocol Echo Response message fromthe mobile station; storing a first stop time; and computing a wirelessaccess latency based on the first start time and the first stop time. Ina related embodiment, the method further comprises the packet dataserving node storing a second start time; transmitting, to a home agent,a Mobile IP Registration Request message; receiving a Mobile IPRegistration Reply message from the home agent; storing a second stoptime; and computing an internet access latency based on the second starttime and the second stop time. In another related embodiment, the stepof computing the internet access latency further comprises adjusting theinternet access latency for a processing time associated with the homeagent.

The system comprises a mobile station and a packet data serving node.The packet data serving node is adapted for wirelessly communicatingwith the mobile station, transmitting a link control protocol echomessage to the mobile station, receiving a link control protocolresponse message from the mobile station, and computing an elapsed timefrom transmission of the link control protocol echo message to receiptof the link control protocol response message to determine the wirelessaccess latency. In a related embodiment, the system comprises a homeagent and a packet data serving node for communicating with the homeagent. The packet data serving node is adapted for transmitting a mobileinternet protocol registration request message to the home agent,receiving a mobile internet protocol registration reply message from thehome agent, and computing an elapsed time from transmission of themobile internet protocol registration request message to receipt of themobile internet protocol registration reply message to determine theinternet access latency.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention and itsadvantages will be readily apparent from the following DetailedDescription taken in conjunction with the accompanying drawings.Throughout the accompanying drawings, like parts are designated by likereference numbers and in which:

FIG. 1 is a schematic illustration of a data network in accordance withthe present invention;

FIG. 2 is a flow diagram illustrating a message sequence for measuringwireless access latency in a Simple IP network in accordance with thepresent invention; and

FIGS. 3A and 3B are flow diagrams illustrating a message sequence formeasuring internet access latency and wireless access latency in aMobile IP network in accordance with the present invention.

DETAILED DESCRIPTION

FIG. 1 schematically illustrates a representative environment of thepresent invention. A mobile station (MS) 100 (e.g., a cellular phone ora wireless data terminal) is wirelessly connected to a base station (BS)105 via a radio frequency (RF) network. The base station 105 isconnected to a base station controller (BSC) 110, typically via awire-line, such as a T1 line. The base station controller 110 isconfigured for connecting to and controlling multiple base stations 105.The base station controller 110 is connected to a Packet ControlFunction (PCF) 115, which typically resides proximate the base stationcontroller 110. The base station controller 110 is also connected to aMobile Switching Center (MSC) 120, which is connected to a Home LocationRegister (HLR) 125.

The PCF 115 is connected to a mobility agent, such as a packet dataserving node (PDSN) 130 via the data network using the Radio Protocol(RP). The PDSN 130 is connected to an accounting authentication andauthorization (AAA) server 135 via the data network using the RemoteAuthentication Dial In User Service (RADIUS) protocol. In a Simple IPnetwork the PDSN 130 is connected to an Internet Protocol (IP) network,such as the Internet. In a Mobile IP system, the PDSN 130 is alsoconnected to a Home Agent (HA) 145 via the data network 140, usingMobile IP protocol.

In one embodiment, the PDSN 130 provides the mobile station 100 withaccess to the Internet, intranets and application servers utilizing acdma2000 Radio Access Network. The PDSN 130 is capable of performing twobasic functions: (1) exchanging packets with the mobile station 100 overthe RF network, and (2) exchanging packets with other IP networks 140.The PDSN 130 is capable of interfacing with the AAA server 135 toprovide the mobile station 100 with a gateway to the IP network 140.

In Mobile IP applications, wherein the mobile station 100 is capable ofroaming outside of its home network, the PDSN 130 is capable ofinterfacing with home agents (HA) 145. An HA 145 is typically a routerlocated on the mobile station's home network, which is capable oftunneling packets to the mobile station while it is away from the homenetwork. The PDSN 130 is capable of acting as a foreign agent (FA) onbehalf of home agents to enable service providers to provide Mobile IPservices to roaming mobile stations 100. The FA can register the mobilestation 100 with their particular HA 145 and provide a forwardingaddress for data delivery. The PDSN/FA 130 is typically a router locatedon a foreign network that is capable of de-tunneling the packets fromthe HA 145 and providing the packets to the mobile station 100 via theRF network.

In data applications, a data call is typically routed through a voicenetwork. The Mobile Switching Center 120, in conjunction with the a HomeLocation Register (HLR) 125 determines that the call is a data call andsends the call back to the Base Station Controller 110, which thenroutes the call through the PDSN 130 to the data network 140.

FIG. 2 illustrates a message sequence for measuring wireless accesslatency in a simple IP network. In one embodiment of the presentinvention, a radio access node or mobility agent like the PDSN canperform measurement of wireless access latency. The radio access nodecan compute a round trip delay between itself and the mobile station bymeasuring a time interval from the time the radio access node sends amessage to the mobile station to the time the radio access node receivesa response from the mobile station. In one embodiment, the message andresponse are provided by a communications standard for use between theradio access node and the mobile station. In a preferred embodiment, themessage and response are control plane messages which do not affectsession data usage (billable bytes over bearer) and thus do not increasethe end user charges.

In a preferred embodiment wherein the radio access node is a PDSN 130utilizing cdma2000 in accordance with the TIA/IS 835-B standard, thePDSN 130 utilizes link control protocol (LCP) messages as outlined inTIA/IS 835-B to measure the wireless access latency. The round tripdelay or FA to MS Latency Time in milliseconds (FMLT), is the timeinterval measured from the time the PDSN/FA 130 sends the mobile station100 an LCP Echo Request message to the time the PDSN/FA 130 receives theLCP Echo Response message from the mobile station 100.

The TIA/IS 835-B standard provides for the LCP Echo Request and Responsemessages. Thus, the PDSNs 130 and mobile stations 100 support the LCPmessages. The TIA/IS 835-B standard outlines using these LCP messagesonly in the context of detecting mobile station 100 availabilityfollowing point-to-point protocol (PPP) session inactivity. The presentinvention, however, advantageously uses these LCP messages to measurewireless access latency. Utilizing messages provided for by the standardallows the system and method of the present invention to be compatiblewith existing standards, and further, to be backward compatible withexisting deployed solutions. Using messages provided by the standardsimplifies implementation in the currently deployed wireless networkinfrastructure equipment and also minimizes taxing the networkinfrastructure.

The LCP Echo messages can be sent to the mobile station 100 and used tomeasure wireless access latency under the following conditions: (1) whena point-to-point protocol (PPP) session is successfully established; (2)when the PPP Inactivity Timer expires; and optionally, (3) when aconfigurable Wireless Access Latency Timer in the PDSN expires.

In one embodiment, an LCP Echo Request/Response message exchange is sentwhen the PPP connection is established. While this message exchange isprovided for by the TIA/IS 835-B standard, the present inventionadvantageously monitors both the time that the LCP Echo Request messageis sent and the time that the LCP Echo Response message is received inorder to measure the wireless access latency. The elapsed time (inmilliseconds) from the sending of the LCP Echo Request message to thereceipt of the LCP Echo Response message can then be recorded in theFMLT parameter for transmission to the AAA server 135. Repeatedexchanges of these messages between the mobile station 100 and the PDSN130 can then be sent when the PPP Inactivity Timer expires, andoptionally, when the Wireless Access Latency Timer expires.

The Wireless Access Latency Timer is not provided by the TIA/IS 835-Bstandard, but can be implemented in the PDSN 130 and used to trigger thewireless access latency measurement. The PPP Inactivity Timer isprovided in the TIA/IS 835-B standard, and can be used in addition to orinstead of the Wireless Access Latency Timer (depending on whether theWireless Access Latency Timer is implemented) to trigger the LCP EchoRequest message to the mobile station 100 after a PPP session isestablished. Because these timers are configurable in the PDSN 130, theservice provider can have complete control over the number of samplesdesired to compute latency at the user session level.

The RADIUS protocol provides for a Usage Data Record (UDR) havingcertain parameters, which can be used for accounting and billingpurposes. In one embodiment, start, stop, and interim usage data recordsare transmitted from the PDSN to the AAA server at the start of acommunications session, at the end of the communications session, andduring the communications session.

The RADIUS protocol also allows new parameters to be added to the UDR.In one embodiment, the PDSN 130 is capable of adding a new accountingparameter attribute, the FMLT (also part of this invention), as a fieldin the Usage Data Record (UDR) of the PDSN 130. The PDSN 130 can thensend the UDR, containing the FMLT information, to the AAA server 135.The FMLT accounting parameter can be added, for example, in a Quality ofService section of the UDR. By adding the FMLT parameter to the UDR,latency information can thus be recorded in the AAA server 135 on aper-user, per-session basis. Recording of latency information can beadvantageously performed in the context of an existing framework. TheAAA server 135 can store the FMLT information for further processing byother network management entities (e.g., for billing, statistical and/orreporting purposes).

The LCP Echo Request/Response messages are control plane messages andthus will not be included as part of the data bearer usage calculations.Using the LCP messages to measure latency will not affect a user'ssession data usage and the user will not be billed for these messages.

The process for measuring Wireless Access Latency proceeds as follows.Once the PPP setup between the mobile station 100 and the PDSN/FA 130has been completed (step 200), the PDSN/FA 130 sends a RADIUS AccountingRequest Start message to the AAA server 135 (step 205). The AAA server135 responds with a RADIUS Accounting Response message to the PDSN/FA130 (step 210). The PDSN/FA 130 then gets and stores the current timestamp for this session in a StartTime parameter (step 215). The PDSN/FA130 sends the LCP Echo Request message to the mobile station 100 (step220). The mobile station 100 receives the LCP Echo Request message and,in response, returns the LCP Echo Response message to the PDSN/FA 130.

The PDSN/FA 130 receives the LCP Echo Response message (step 235) andgets and stores the current time stamp for this session in a StopTimeparameter (step 240). The PDSN/FA 130 then computes the Wireless AccessLatency using the StartTime and StopTime parameters (step 245). Thecomputed Wireless Access Latency is then assigned to an FMLT accountingparameter in, for example, a UDR of the PDSN 130. The PDSN 130 can thensend the UDR with the FMLT parameter to the AAA server 135 in a RADIUSAccounting Request message (step 255). Once the message has beenreceived, the AAA server 136 returns a RADIUS Accounting Responsemessage to the PDSN 130 (step 260). No new functionality is required tobe in the AAA server 135. The AAA server 135 can simply store the UDRfor further processing by other network management entities.

FIGS. 3A and 3B illustrate a message sequence for measuring latency in amobile IP session. In mobile IP, an IP address of the mobile station 100is anchored at its home agent (HA) 145. The mobile station 100 is thusable to keep the same IP address, and its connectivity to the network,as it moves from one PDSN 130 to another. The mobile station's HA 145forwards messages destined for the mobile station 100 to a foreign agent(FA) 130 via a Mobile IP network. The FA 130 then routes the messages tothe mobile station 100 using the RF network.

Two types of latency exist in Mobile IP networks: Wireless AccessLatency and Internet Access Latency. Wireless Access Latency is measuredusing the FMLT parameter discussed above. Internet Access Latency can bemeasured by utilizing messages transmitted between the FA 130 and the HA145 (in accordance with a communications standard), taking into accountany processing time required by the HA 145 before responding to themessage.

In one embodiment, the messages used for measuring Internet AccessLatency are control plane messages which do not affect session datausage (billable bytes over bearer) and thus do not increase the end usercharges. In a preferred embodiment, Internet Access Latency can bemeasured using Mobile IP (MIP) Registration messages outlined in TIA/IS835-B. Utilizing messages provided for by the standard allows the systemand method of the present invention to be compatible with existingstandards, and further, to be backward compatible with existing deployedsolutions. Using messages provided by the standard simplifiesimplementation in the currently deployed wireless network infrastructureequipment and also minimizes taxing the network infrastructure.

In the context of Internet Access Latency, the round trip delay or FA toHA Latency Time in milliseconds (FHLT), is the time interval measuredfrom the time the PDSN (acting as an FA) 130 sends the HA 145 a MobileIP (MIP) Registration Request Message to the time the PDSN/FA 130receives the MIP Registration Reply message from the HA 145. The HA 145may require some processing time to process the MIP Registration RequestMessage, before returning the MIP Registration Reply message. If so, theprocessing time required by the HA 145 (or an estimate of the processingtime) can be subtracted from the total round trip delay to arrive at theFHLT. The MIP Registration Request/Reply messages are provided in TIA/IS835-B for establishing and maintaining a Mobile IP user session betweenthe mobile station 100 and the HA 145. The present invention, however,advantageously uses these MIP Registration messages to measure Internetaccess latency up to the edge of the service provider network where theHA node is located. In general the MS, based on TIA/IS 835-B, willregister with the HA:

After receiving an Agent Advertisement from the PDSN due to initialestablishment of a PPP session with this PDSN; and

Before expiration of the MIP Lifetime timer in the PDSN and HA.

In one aspect of the invention for a Mobile IP scenario, the LCP Echomessages are used to measure wireless access latency as was the case forSimple IP under the following conditions: (1) after reception of MobileIP Registration Reply; (2) when the PPP Inactivity Timer expires; andoptionally, (3) when a configurable Wireless Access Latency Timer in thePDSN expires.

The Wireless Access Latency Timer is not provided by the TIA/IS 835-Bstandard, but can be implemented in the PDSN 130 and used to trigger thewireless access latency measurement. The PPP Inactivity Timer isprovided in TIA/IS 835-B standard, and can be used in addition to orinstead of the Wireless Access Latency Timer (depending on whether theWireless Access Latency Timer is implemented) to trigger the LCP Echomessage to the MS. Because these timers are configurable in the PDSN130, the service provider can have complete control over the number ofsamples desired to compute latency at the user level.

In one embodiment, the PDSN 130 is capable of adding a new accountingparameter attribute, the FHLT (round trip delay from FA to HA inmilliseconds), to the Usage Data Record (UDR) of the PDSN 130. The PDSN130 can then send the UDR, containing the FHLT information (andoptionally the FMLT information), to the AAA server 135. The FHLTaccounting parameter can be added, for example, in a Quality of Servicesection of the UDR. By adding the FHLT parameter to the UDR, latencyinformation can thus be recorded in the AAA server 135 on a per-user,per-session basis and in the context of an existing framework. The AAAserver 135 can store the FHLT information (and optionally the FMLTinformation) for further processing by other network management entities(e.g., for billing, statistical and/or reporting purposes).

The MIP Registration messages are control plane messages. Thus, themessages will not be included, as part of the data bearer usagecalculations and the user will not be billed for these messages.

The process for measuring wireless and internet access latency in amobile IP network proceeds as follows. Once the PPP setup between themobile station 100 and the PDSN/FA 130 has been completed (step 300),the FA 130 advertises its existence to the mobile station 100 (step305). The mobile station 100 is thus able to discover whether it is athome or away from home depending on whether it is communicating with anHA 145 or a FA 130. The mobile station 100 then sends an MIPRegistration Request to the PDSN/FA 130 (step 310). The PDSN/FA 130 thenauthenticates the MS using a RADIUS Access Request message to the AAAserver 135 (step 315). The AAA server 135 responds with a RADIUS AccessAccept message (step 320).

The PDSN/FA 130 gets and stores the current time stamp for this sessionin a StartTime parameter (step 325) and sends an MIP RegistrationRequest to the HA 145 (step 330). The HA 145 receives the MIPRegistration Request and, after processing the request (step 335),returns an MIP Registration Reply message to the PDSN/FA 130. ThePDSN/FA 130 receives the MIP Registration Reply message (step 340) andgets and stores the current time stamp for this session in a StopTimeparameter (step 345). The PDSN/FA 130 then computes the Internet AccessLatency using the StartTime and StopTime parameters, adjusting theresult by an estimate of the time required by the HA to process therequest (i.e, the estimated HA processing time) (step 350). The computedInternet Access Latency is then assigned to an FHLT accounting parameterin, for example, a UDR of the PDSN/FA 130. After the PDSN/FA 130receives the MIP Registration Reply from the HA 145, the PDSN/FA 130sends the MIP Registration Reply to the mobile station 100 (step 355).

The PDSN/FA 130 then sends a RADIUS Accounting Request Start messagecontaining the FHLT parameter to the AAA server 135 (step 360). The AAAserver 1350 responds with a RADIUS Access Accept message (step 365). ThePDSN/FA 130 gets and stores the current time stamp for this session in aStartTime parameter (step 370). The PDSN/FA 130 then sends the LCP EchoRequest message to the mobile station 100 (step 375). The mobile station100 receives the LCP Echo Request message and, in response, returns theLCP Echo Response message to the PDSN/FA 130. The PDSN/FA 130 receivesthe LCP Echo Response message (step 380) and gets and stores the currenttime stamp for this session in a StopTime parameter (step 385).

The PDSN/FA 130 then computes the Wireless Access Latency using theStartTime and StopTime parameters (390). The computed Wireless AccessLatency is then assigned to the FMLT (FA to MS Latency Time inmilliseconds) accounting parameter in, for example, a UDR of the PDSN130. The PDSN 130 can then send the FMLT to the AAA server 135 in aRADIUS Accounting Request message step 395). Once the message has beenreceived, the AAA server 135 returns a Radium Accounting Responsemessage to the PDSN 130 (step 400).

The latency measurements described herein, including the wireless accesslatency and the internet access latency measurements provide a way tomeasure and record user experience in conducting a data call. Thesemeasurements can also be used as a way to measure the effect on userexperience, if any, of new equipment that is introduced into thenetwork. Using control plane messages to measure latency provides anadvantage in that the customer's data usage is not affected. Thus, nobilling system changes in the service provider network are needed toincorporate this functionality. Further, by determining latency andtherefore quality of service at a per user, per session level, thepresent invention makes it possible for a service provider to bill auser for providing a particular promised quality of service.

By measuring latency at a per user per session level, a service providercan determine and improve the quality of its wireless infrastructure,and can further improve the user's experience. Certain technologies,such as Voice over IP (VoIP), real time streaming, etc., that areparticularly susceptible to latency will benefit from the ability tomeasure latency at the user session level.

Although the present invention has been fully described by way ofexamples and with reference to the accompanying drawings, it is to beunderstood that various changes and modifications will be apparent tothose skilled in the art without departing from the spirit and scope ofthe invention. Therefore, unless such changes and modifications departfrom the scope of the present invention, they should be construed asbeing included therein.

1. A method for measuring latency between a first device and a seconddevice, said first and second devices communicating in accordance with acommunications specification, said method comprising: transmitting,during a communication session between said first and second devices, amessage from said second device to said first device, said messageprovided by said communications specification; receiving a responsemessage from said first device, said response message provided by saidcommunications specification; computing an elapsed time fromtransmission of said message to receipt of said response message todetermine said latency; and recording said latency in a latencyparameter in a data record.
 2. A method in accordance with claim 1,wherein said message and said response message are control planemessages.
 3. A method in accordance with claim 1, wherein said messageand said response message do not affect a session data usage of a userof said first device.
 4. A method in accordance with claim 1, furthercomprising: transmitting said data record containing said latencyparameter to an application server.
 5. A method in accordance with claim1, wherein said data record is provided by said communicationsspecification, said method further comprising: adding said latencyparameter to said data record.
 6. A method in accordance with claim 1,wherein said first device and said second device are adapted tocommunicate wirelessly using said communications specification.
 7. Amethod in accordance with claim 1, wherein said first device and saidsecond device are adapted to communicate via a wire-line portion of awireless network using said communications specification.
 8. A method inaccordance with claim 1, wherein said first device is a mobile stationand said second device is a mobility agent.
 9. A method in accordancewith claim 1, wherein said first device is a home agent and said seconddevice is a mobility agent.
 10. A method in accordance with claim 1,wherein said message and said response message are link establishmentprotocol messages.
 11. A method in accordance with claim 1, wherein saidstep of transmitting is performed after said communication session hasbeen established.
 12. A method in accordance with claim 1, wherein saidstep of transmitting is performed upon the expiration of a timer.
 13. Amethod in accordance with claim 12, wherein said timer is provided bysaid communications specification.
 14. A method in accordance with claim12, wherein said timer is not provided by said communicationsspecification, said method further comprising: implementing said timerin said second device, said timer configured to expire during saidcommunication session.
 15. A method in accordance with claim 1, whereinsaid communication session is a data call.
 16. A method, performed by apacket data serving node, for measuring latency, comprising: storing afirst start time; transmitting, to a mobile station, a Link ControlProtocol Echo message; receiving a Link Control Protocol Echo Responsemessage from said mobile station; storing a first stop time; andcomputing a wireless access latency based on said first start time andsaid first stop time.
 17. A method in accordance with claim 16, whereinsaid step of transmitting is performed during a communication sessionbetween said packet data serving node and said mobile station.
 18. Amethod in accordance with claim 17, wherein said step of transmitting isperformed upon expiration of a timer.
 19. A method in accordance withclaim 18, further comprising: implementing said timer in said packetdata serving node, said time configured to expire during saidcommunication session.
 20. A method in accordance with claim 16, whereinsaid packet data serving node and said mobile station are configured tocommunicate in accordance with a communications specification.
 21. Amethod in accordance with claim 20, wherein said communicationsspecification provides for a data record, said method furthercomprising: adding a wireless access latency parameter to said datarecord; and recording said wireless access latency in said wirelessaccess latency parameter.
 22. A method in accordance with claim 16,further comprising: storing a second start time; transmitting, to a homeagent, a Mobile IP Registration Request message; receiving a Mobile IPRegistration Reply message from said home agent; storing a second stoptime; and computing an internet access latency based on said secondstart time and said second stop time.
 23. A method in accordance withclaim 22, wherein said step of computing said internet access latencyfurther comprises adjusting said internet access latency for aprocessing time associated with said home agent.
 24. A method inaccordance with claim 22, wherein said step of computing said internetaccess latency further comprises adjusting said internet access latencyfor an estimated processing time associated with said home agent.
 25. Amethod in accordance with claim 22 wherein said packet data serving nodeand said home agent are configured to communicate in accordance with acommunications specification, said communications specificationproviding for a data record, said method further comprising: adding aninternet access latency parameter to said data record; and recordingsaid internet access latency in said internet access latency parameter.26. A system for measuring latency comprising: a first device; and asecond device adapted for communicating with said first device inaccordance with said communications specification and for transmitting amessage to said first device, receiving a response message from saidfirst device, computing an elapsed time from transmission of saidmessage to receipt of said response message to determine said latency,and recording said latency in a latency parameter in a data record;wherein said message and said response message are provided by saidcommunications specification.
 27. A system in accordance with claim 26,wherein said second device is adapted for transmitting said message tosaid first device during a communication session between said first andsecond devices.
 28. A system in accordance with claim 27, wherein saidcommunication session is a data call.
 29. A system in accordance withclaim 26, wherein said message and said response message are controlplane messages.
 30. A system in accordance with claim 26, wherein saidmessage and said response message do not affect a session data usage ofa user of said first device.
 31. A system in accordance with claim 26,further comprising: an application server connected to said seconddevice, said second device further adapted for transmitting said datarecord containing said latency parameter to said application server. 32.A system in accordance with claim 26, wherein said data record isprovided by said communications specification, said second devicefurther adapted for adding said latency parameter to said data record.33. A system in accordance with claim 26, wherein said first device andsaid second device are adapted to communicate wirelessly using saidcommunications specification.
 34. A system in accordance with claim 26,wherein said first device and said second device are adapted tocommunicate via a wire-line portion of a wireless network using saidcommunications specification.
 35. A system in accordance with claim 26,wherein said first device is a mobile station and said second device isa mobility agent.
 36. A system in accordance with claim 26, wherein saidfirst device is a home agent and said second device is a mobility agent.37. A system in accordance with claim 26, wherein said message and saidresponse message are link establishment protocol messages.
 38. A systemin accordance with claim 26, wherein said second device is adapted totransmit said message upon the expiration of a timer.
 39. A system inaccordance with claim 38, wherein said timer is provided by saidcommunications specification.
 40. A system for measuring wireless accesslatency comprising: a mobile station; and a packet data serving node forwirelessly communicating with said mobile station, said packet dataserving node adapted for transmitting a link control protocol echomessage to said mobile station, receiving a link control protocolresponse message from said mobile station, and computing an elapsed timefrom transmission of said link control protocol echo message to receiptof said link control protocol response message to determine saidwireless access latency.
 41. A system in accordance with claim 40,wherein said packet data serving node is adapted for transmitting saidmessage to said first device during a communication session with saidmobile station.
 42. A system in accordance with claim 40, wherein saidpacket data serving node is adapted for transmitting said message tosaid first device upon expiration of a timer.
 43. A system in accordancewith claim 40, wherein said link control protocol echo message and saidlink control protocol echo response message are provided by acommunications specification.
 44. A system in accordance with claim 43,wherein said communications specification provides for a data record,said packet data serving node further adapted for adding a wirelessaccess latency parameter to said data record and recording said wirelessaccess latency in said wireless access latency parameter.
 45. A systemfor measuring internet access latency comprising: a home agent; and apacket data serving node for communicating with said home agent, saidpacket data serving node adapted for transmitting a mobile internetprotocol registration request message to said home agent, receiving amobile internet protocol registration reply message from said homeagent, and computing an elapsed time from transmission of said mobileinternet protocol registration request message to receipt of said mobileinternet protocol registration reply message to determine said internetaccess latency.
 46. A system in accordance with claim 45, wherein saidpacket data serving node is further adapted for adjusting said internetaccess latency for a processing time associated with said home agent.47. A system in accordance with claim 45, wherein said packet dataserving node is further adapted for adjusting said internet accesslatency for an estimated processing time associated with said homeagent.
 48. A system in accordance with claim 45, wherein said mobileinternet protocol registration request message and said mobile internetprotocol registration reply message are provided by a communicationsspecification.
 49. A system in accordance with claim 48, wherein saidcommunications specification provides for a data record, said packetdata serving node further adapted for adding an internet access latencyparameter to said data record and recording said internet access latencyin said internet access latency parameter.